Sound record



July 12, 1938.

p. VON MIHALY SOUND? RECORD Filed March 28, 1929 /n ventar: 0. I Wh hq Patented July 12, 1938 UNITED STATES 2.12am SOUND asooan Dnes v on Mihaly, Berlin-Wilmersdorf, Germany.

assignor to the firm Julius Pintsch Aktiengesellschaft, Berlin, Germany Application March 28, 1929, Serial No. 350,692

In Germany December 8, 1928 '1 Claims. (01. 214-415) Various sound records upon film sensitive to light are already known, as well as apparatus forthe production of such films and apparatus for the reproduction of the records. The oldest of these devices consists in influencing the light of an arc lamp inductively by microphone currents and allowing the varying light of the arc lamp to act through a slit upon a sensitive film moving rapidly past it. To the sound vibrations in there correspond varying bright and dark strips upon the film. If such a film is passed, in front of a constant source of light, and the rays of the source of light darkened to a varying extent by the variations in the depth of the blackening ii of the film are thrown upon a cell which is sensi tive to light and which is connected in a joint circuit with a telephone, corresponding variations in the resistance of the sensitive cell are produced and corresponding variations of current in 90 the telephone, so that the sound originally recorded can again be heard.

The advantages of such a reception and reproduction of sound, as compared with those of a disctalking machine are immediately obvious.

25 Since both the recording and the reproduction are effected by means of a ray of light no wear of the sound record carrier can occur. Further- 85 into the other at one point of the film. This arrangement has the advantage as compared with the known arrangement in which the sound record runs along a spiral line, that when the film breaks the same can be stuck together without 40 difiiculty whilst this is not possible with the known arrangement, since in that case theends of the sound record will no longer correspond to one another.

It is also known to provide films with a plu- M rality of record strips being parallel to one another and to the edges of the film. However, such records are not continuous and for reproducing the film has to be moved alternately in opposite directions which involves a complicated 50 driving mechanism and causes interruptions of the sound reproduction at the end of each strip. The accompanying drawing illustrates by way of example a sound record according to the present invention. 55 Figure 1 is a perspective view of an endless band of film provided with a sound record according to the invention.

Fig. 2 is an enlarged detail in plan of a part of the film shown in Fig. 1.

Referring to the drawing in detail, the endless 5 I the film, the record shifting at intervals and passing completely around the film between two such displacements.

These lines form a plurality of sound track sections which are disposed generally longitudinally of the film and the shifting of the record forms crossover or bridging sections 4 connecting the end of one sound track section with the beginning of another sound track section.

What I claim is:-

1. A sound record for talking machines and the like, consisting of an endless band of light sensitive film on which sound has been photographically recorded in lines extending a number of times around the endless band parallel to the edges of the film, the record shifting from one line to the next at intervals and passing completely round the endless band between two such displacements.

2. An endless transparent light-sensitive standard type motion picture film having a photographic sound record thereon, said record being of a width less than that of said film, said record comprising a plurality of portions paralleling and 5 adjacent each other and paralleling the edges 01 the film, said portions being joined to form a single record.

3. An endless transparent light-sensitive standard type motion picture film having a pho- 4o tographic sound record thereon, said record being of a width less than that of said film, said record comprising a plurality of portions paralleling and adjacent each other and paralleling the edges of including diagonal bridging sections between the successive parallel portions, the whole forming a single record.

5. An endless transparent light-sensitive standard ty'pe motion picture fllm having a photographic sound record thereon, said record being oi' a width less than that of said film, said record comprising a plurality of portions paralleling and adjacent each other and paralleling the edges 0! the iilm, said portions including rectilinear 10 bridging sectionsgbetween the successive parallel portions, the whole forming a single record.

8. In a transparent light-sensitive endless film a single narrow photographic sound record thereon and disposed in parallel sections, said sound record including integral crossover sections between the; said several parallel sections.

. 7. A transparent light-sensitive endless iilm, including a unitary photographic sound record 

